My family also started a small greenhouse last year. Learning about the
different insects that invade the house isn't all fun and games but with
help from others it can become much easier. This insects you call whitefies
were around our hibiscus's and datura's too. It is true that Sevin and
Malathion won't work believe me we have tried. The best thing to do is to keep
your house closed at all times and extinguish the current bugs with a leading
household bug killer. They seem to work wonders. This seems hectic and
unipropriate but will eventually pay off when your greenhouse is full with
beautiful plantlife.Good luck.